Device for actuating double seat valves

ABSTRACT

The invention relates to a device for actuating double seat valves, which are especially suitable for the food and beverage industry and which have an independently actuated first closing element ( 3 ), which is designed as a sliding piston and a fully dependent on this actuated second closing element ( 4 ), which is designed as a seat disc, whereby the actuator ( 100, 200 ) produces at all times using a main adjustment device ( 100 ) for the fully open position (H) as well as, for the case of maximum requirements, the respective individual adjustment devices ( 200; 200.1, 200.2 ) which are assigned to the closing elements ( 3, 4 ) for generation of the partially open positions (T 1,  T 2 ) acting in opposite directions for the seat cleaning of the closing elements ( 3, 4 ). The object of the invention is to design a device according to this generic type in such a manner that it is constructed as simply as possible and is easily and economically adjustable to the various requirements which are put onto a double seat valve of the type in discussion (only full opening stroke or full opening stroke as well as seat cleaning partial strokes). This is thus achieved in that the individual adjustment devices ( 200; 200.1, 200.2 ) are designed stand-alone and are additively inserted between the main adjustment device ( 100 ) and a valve housing ( 1 ), that the third working piston ( 206;206/206.1 ) is positioned able to be moved axially on the second control rod ( 4   a,    204 ) which is designed as a hollow rod, and encloses the first control rod ( 3   a,    203 ) and is able to be brought in the direction of the second partially open position (T 2 ) in a clamped connection, that the second actuating piston ( 205 ) is tightly connected on one side with the first control rod ( 3   a,    203 ) which adjusts the first closing element ( 3 ), that it is otherwise directly or indirectly positioned able to be moved axially on a first actuator stem ( 103 ) of the main adjustment device ( 100 ) and is able to be brought with this in the direction of the fully open position (H) in a clamping connection, and that it is able to be loaded with pressurizing medium on each of its two piston surfaces ( FIG. 2 ).

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable

BACKGROUND OF THE INVENTION

Prior Art

A device according to this generic type is known from EP 0 868 619 B1.The device diagrammed in FIG. 6 and explained briefly in the attacheddescription is in fact not subject matter of the patent claims of thispublication, however the features disclosed prove how through simplemodification to the protected actuating device 1 (reference numbers ofthe figures therein) a double seat valve can be activated, whoseindependently actuated first closing element 4 is designed as a slidingpiston with radial sealant and whose dependently actuated second closingelement 5 is designed as a seat disc. In this closing elementconfiguration the partially open position T1 of the first closingelement 4 is completed in the opposite direction to the opening strokeH, which is directed upwards relative to the diagrammed position of thevalve. For execution of the partially open position T1 a main piston 106of the main adjustment device 1 a is loaded from above with pressurizingmedium D2 using a non-specified pressurizing medium connection. Thepartial stroke limit downwards of the first closing element 4 occurs inthat a valve stem 104 takes its bearing on the latter through anon-specified recess above a spring abutment 119. The partially openposition T2 of the attached actuated second closing element 5, whichonly has a freedom of motion upwards due to its design as a seat disc,is done using a piston 108, which is loaded with pressurizing medium D3using a first pressurizing medium connection 117. The synchronization ofa hollow bar 105 connected with the second closing element 5 upwards isdone using its hollow bar head 105 a. The partial stroke limit of thepiston 108 is implemented through a second recess 114 a on the stopsleeve 114.

The preceding briefly described actuator is also designated in expertcircles as a so-called “integrated” actuator, because it accommodatesthe main adjustment device 1 a for the full opening stroke H as well asthe individual adjustment devices 1 b, 1 c for the partially openpositions T1 and T2 in a common housing. These types of actuators are asa rule compactly built and make it possible to arrange a so-calledcontrol module and/or control head 8 (FIG. 1) directly above the mainadjustment device 1 a, if the individual adjustment devices 1 b, 1 c arearranged in the previously described manner in reference to the mainadjustment device 1 a.

The significant disadvantages of the integrated actuators arise alsofrom the fact that they are designed for the maximum requirements whichare placed on double seat valves of the type under discussion. Maximumrequirements are then given if, along with the full opening stroke Hwhich is executed by the main adjustment device, the opposed partiallyopen positions T1, T2 of both closing elements for the execution of therespective seat cleaning, which is carried out by an individualadjustment device assigned to each closing element to be activated, arenecessary. Since a large portion of the double seat valves placed ininstallations in the food and beverage industry are in applicationswithout the possibility or necessity of seat cleaning, because onlymixing efficiency is required, integrated actuators in which only themain adjustment device is activated are normally too complex andtherefore uneconomical. In practice these types of applications thenfall back on “normal” actuators (standard actuators) for double seatvalves, which only accommodate a main adjustment device for the fullopen position H. Thereby the number of integrated actuators from amanufacturer of double seat valves is reduced, since each double seatvalve corresponding to the requested requirements is at best equippedwith a suitable actuator for this purpose and thereby results in anuneconomical number of manufactured integrated actuators as the case maybe.

A further integrated actuator for a double seat valve according to thisgeneric type is known from the EP 1 030 988 B1. The kinematics of thisactuator corresponds in an identical manner to that according to FIG. 6in the EP 0 868 619 B1. In contrast to the latter, in the former thepartial stroke movement T1 opposed to the full opening movement H of theindependently actuated first closing element which is designed as asliding piston is executed by a separate third working piston 30, whichis arranged above the first working piston 18, which causes the fullopening stroke H. The general arrangement is therefore in fact morecomplex, however by the separate third pressure chamber 39 created overthe third working piston 30 the necessary volume for its loading withpressurizing medium is significantly reduced compared to thecorresponding pressure chamber over the main piston in actuation of thedouble seat valve according to EP 0 868 619 B1, whereby lesspressurizing medium is used when switching the assigned partial strokemovement T1 and the actuation reacts quicker to the switching command inthis regard. At the same time the integrated actuator according to EP 1030 988 B1 is in turn also relatively complexly constructed and flawedwith the preceding briefly presented further disadvantages in connectionwith the integrated actuator according to EP 0 868 619 B1.

In DE 31 33 273 C2 it was already proposed for a cleanable double seatvalve with leakage control, to additively insert the individualadjustment devices between the main adjustment device and a lanternhousing under the main adjustment device which exclusively creates thefull stroke for the full open position as the only adjustment devicewithout changing the neighboring standard member. However it isconcerned here with a double seat valve, which has two closing elementsdesigned as seat discs, so that the full stroke H for the full openposition and both partial stroke movements T1, T2 are aligned forgapwise removal of the closing elements from their respective seatsurfaces. These attainable advantages with this so-called “modular”actuator concept especially exist in that to the greatest possibleextent a standardized double seat valve, which has available a standardactuator for the creation of the fully open position through additive ofrelatively simple individual adjustment devices, contains specialfunctions in regards to the previously described creation of partiallyopen positions of both closing elements. From DE 31 33 273 C2 there areno details to be taken on whether the known modular actuator concept isapplicable to double seat valves of the preliminary characterized typeand not at all what this type of solution could look like.

The dependently actuated closing element of the double seat valve, whichis also designated as a double disk with its two seals, is in fact notcritical during the seat cleaning in regards to its partially openposition T2 and can therefore be moved against a fixed stop for theexecution of the aligned seat cleaning position. This stop thereforeneeds no complex pre-adjustment or readjustment. During the seatcleaning the cleaning solution is normally under pressure on thedependently actuated closing element, so that this must be opened by thepartial stroke T2 against the resulting closing force from thecorresponding pressure and the assigned effective surface of thisclosing element. To overcome this closing force or holding down forcethe assigned second individual adjustment device is to be dimensionedaccordingly. Either a sufficiently large piston surface of the actuatingpiston in this second individual adjustment device is to be provided orthe pressure of the pressurizing medium loaded on the actuating pistonis to be correspondingly increased if there are restrictions in regardsto the dimension of the diameter of the actuating piston. An adjustmentof the actuator to the existing pressure conditions using acorresponding dimensioning of the actuating piston is always primarily aquestion of cost and is normally only chosen if other possibilities arenot available. The choice of a higher pressure of the pressurizingmedium is normally preferred; it is however always eliminated inpractice if the installation or plant in which the cleanable double seatvalve is installed does not have a pressure level available in thisregard or out of cost considerations can not be additionally done.

It is the object of the present invention to design a device accordingto this generic type in such a manner that it is constructed as simplyas possible and is easily and economically adjustable to the variousrequirements which are put onto a double seat valve of the type indiscussion (only full opening stroke or full opening stroke as well asseat cleaning partial strokes).

Furthermore in the scope of an advantageous embodiment of the proposeddevice a larger flexibility should be ensured in the adjustment of thesecond individual adjustment device for the partial stroke movement ofthe dependently actuated closing element on the available pressure ofthe pressurized medium.

SUMMARY OF THE INVENTION

One obvious first advantage of the proposed solution lies in that forthe first time a solution is disclosed on how the motion kinematics of adouble seat valve capable of seat cleaning of the type in discussionwith a modular actuator concept is implemented, in which the mainadjustment device has a standard actuator and the individual adjustmentdevices are independently designed and are inserted between the standardactuator and the valve housing or a lantern housing connected with it.For that reason henceforth it is possible to equip double seat valveswhich are capable of seat cleaning and those that are not capable ofseat cleaning with the same standard actuator for the full openingmovement of the valve. Thus on the one hand the best conditions for aneconomic number of production pieces of this type of standard actuatorsprevail and on the other hand for each double seat valve only thecorresponding necessary actuator parts are used.

Furthermore the proposal makes possible the implementation of specialfunctions, namely the execution of the partial stroke movement T1, T2 ofboth closing elements for the purpose of their seat cleaning by means ofstand-alone individual adjustment devices, economically justifiable forinitial equipment of double seat valves, as well as for the refitting ofalready available double seat valves, which were previously normalswitching, however more capable of seat cleaning.

The insertion of stand-alone individual adjustment devices in arelatively complex structure, as is demonstrated in a double seat valve,is therefore possible because the individual members within the scope ofa modular system are normed or standardized in their connections andjoints as far as possible. This is true for the main adjustment device(standard actuator) as well as for the lantern housing adjacent to thevalve housing and the control rods led through from the upper valvehousing member. The housing connection is done preferably usingstandardized so-called clamping ring connections and the control rodsare screwed together at the corresponding locations. Due to thearrangement of the individual adjustment devices between the mainadjustment device and the valve housing, the other side of the mainadjustment device remains free for the arrangement of a control device,which among other things monitors the path of motion and the discreteend locations of the closing elements and takes over the entire controllogic as well as the pilot valve.

A further advantage results from the axial decoupling of the first valvestem, which extends into the area of the individual adjustment devicesin a second actuator stem, connected with the independently actuatedfirst closing element or from the corresponding decoupling of the secondactuating piston permanently axially connected with the first valve stemfrom a first actuator stem which is arranged in the main adjustmentdevice and at the same time reaches into the area of the individualadjustment devices. The partial stroke movement T1 of the independentlyactuated, first closing element which is designed as a sliding pistonopposite to the full opening stroke H of the valve is first possible bythis decoupling.

On the other hand it allows the first executable axially movablepositioning of the second actuating piston by the previously nameduncoupling onto the first actuator stem, this if needed, namely with thefull opening movement to push in the direction of this opening movementso far on the bearing location until it arrives in a clampingconnection. In this clamping connection the second actuating pistonsupports from now on the main adjustment device in the opening stroke H,since the second actuating piston according to the invention is able tobe loaded with pressurizing medium on each of its two piston surfacesand through this can make an additional independent opening forceavailable in the direction of the full opening movement of the doubleseat valve. The second actuating piston and with it the assignedindividual adjustment devices thus have the function of a so-called“batch actuator” in this movement phase of the actuating.

The special actuating kinematics of the proposed device lies in that theforce flow from the second actuating piston can act through the firstactuator stem and the first actuating piston onto the prestress force ofthe main spring. Conversely however it is not possible through the axialdecoupling between the main adjustment device and the individualadjustment devices, to transfer an opening force to the first closingelement from the main adjustment device. An opening of the double seatvalve alone with the help of the main adjustment device is therefore notpossible. It is mandatory for the opening of the double seat valve toalways be done according to specifications through the stroke movementof the first actuating piston, but only then when the second actuatingpiston of the first actuator stem in the main adjustment device followsin the corresponding force supporting trailing action.

Since the second actuating piston, not in a necessary but desirablemanner, has approximately the same piston cross-section as the firstactuating piston in the main adjustment device, the possibility arisesthrough the aforementioned batch function to significantly reduce thesize of the main adjustment device relevant to the opening force (thisis primarily the diameter), whereby among other things a significantcost reduction takes place. On the other hand from the aforementionedcircumstances the possibility arises to actuate the double seat valvewithout reduction of the size ratio of the actuator even with a lowoperating pressure of the pressurized medium.

Both stand-alone individual adjustment devices are built space-savingand compact, if they, as it is proposed, are arranged in a singlehousing designed from two housing members and with their actuatingpistons there form three pressurizing medium chambers actuatingindependently of one another, whereby the second pressurizing mediumchamber between the second actuating piston and the third housingmember, the third pressurizing medium chamber between the thirdactuating piston and the fourth housing member and the fourthpressurizing medium chamber between both of the two actuating pistonsform the individual adjustment devices.

If, as this is further proposed, the first actuator stem of the mainadjustment device leads out through the latter in the direction of theindividual adjustment devices and is guided axially movable there in thefront end of the second actuator stem which is permanently connected tothe first control rod up to a stop face, then it is possible to make thesecond actuating piston out of corrosion resistant light alloy,preferably out of aluminum. This would furthermore be proposed for theother actuating pistons as well, due to cost and weight saving reasons.

For easier adjustment of the actuator of the second individualadjustment device, which is assigned to implement the partial stroke T2for the dependently actuated closing element, a different, however aboveall relatively low pressure of the pressurized medium provides a furtherembodiment of the proposed device, that the third actuating piston isfixed, however able to be loosened, on its side toward the secondactuating piston with a smaller diameter additional piston, that theadditional piston working together with a housing ring fixed on thehousing of the individual adjustment devices forms a fifth pressurizingmedium chamber, which is connected with a third pressurizing mediumchamber formed between the third actuating piston and the fourth housingmember, and that with the introduction of a third pressurizing mediumflow to the third pressurizing medium chamber also additionally in thefifth pressurizing medium chamber an additional force results affectingthe additional piston, which additively superimposes on the forceaffecting the third actuating piston. Through the arrangement of anadditional piston on the actuating piston of the second individualadjustment device the latter gains a function, which is also oftendesignated as a so-called “batch function”. The actuating pistonexperiences quasi a surface enlargement through the additional piston,which indeed does not have the effect of a larger diameter pistonsurface by the chosen arrangement, but rather is found in a second,parallel plane. In the present case the pressurizing medium reaches theactuating piston first and finally the additional piston, in order eachtime to develop a force on the respectively arranged pistons through theinstalled piston surfaces, whereby these two forces, the force on theactuator pistons and the additional force on the additional pistons areadditively superimposed on each other.

A compact arrangement of the second individual adjustment device withadditional pistons is attained according to a further proposal, in thatthe additional piston has a larger diameter external piston section anda smaller diameter interior piston section, that the interior pistonsection is sealed on the face side against the third actuating pistonand bolted to it, that the exterior piston section is sealed on thecircumference against the shell of a cylindrical cutout in the housingring and the interior piston section is sealed on the circumference in acoaxial through-bore in the housing ring, and that in the connectionarea of the third actuating piston with the additional piston arearranged in the former a first pressurizing medium channel and in thelatter a second pressurizing medium channel, which correspond with oneanother and connect the third pressurizing medium chamber and the fifthpressurizing medium chamber with one another permeable to thepressurizing medium. The housing ring which is fixed in the housing ofthe individual adjustment devices forms on the one hand, with theadditional pistons, the necessary additional fifth pressurizing mediumchamber and creates on the other hand through its housing side support,the physical conditions for the addition of the additional force to theforce on the third actuating piston. The latter borders the thirdpressurizing medium chamber in connection with the fourth housingmember, in which the third pressurizing medium flow is first introducedin order to then finally reach into the fifth pressurizing mediumchamber.

According to a further advantageous embodiment the housing ring has aradial projection on the circumferential side, with which the housingring is arranged form fit to the connection area between the third andthe fourth housing member. The assembly of the housing ring is simpleunder these conditions, since the latter is inserted in the third andthe fourth housing member, before these are then connected with oneanother, preferably integrally joined. It shall be understood that alsoa detachable connection between the third and the fourth housing membercan be made.

The device according to the invention is designed either with or withoutadditional pistons. Since it is an advantage for the housing of theindividual adjustment devices with the pressurizing medium connectionwhich comes into question to always be designed identically regardlessof whether an additional piston is present or not, a further embodimentof the proposed device is designed, that a fourth pressurizing mediumconnection for an alternative first pressurizing medium flow for loadingthe second actuating piston which is arranged in the third housingmember discharges into an upstream fourth pressurizing medium chamber inthe area between the third actuating piston and the housing ring, andthat the upstream fourth pressurizing medium chamber is connected with afourth pressurizing medium chamber designed between the second actuatingpiston on the one hand and the housing ring in connection with theadditional piston on the other hand through at least one connectionchannel, which is arranged in one of the cylindrical cutout outsideencompassing part of the housing ring. Through this arrangement thefourth pressurizing medium connection can remain on any position in thehousing of the individual adjustment devices on which it is arranged ifthe second individual adjustment device is not equipped with anadditional piston. The connection channel in the housing ring ensuresthe permeability for the pressurizing medium, so that the pressurizingmedium introduced through the fourth pressurizing medium connection canget from one side of the housing ring to its other side under the secondactuating piston.

The relatively simply designed total actuator, which experiences aclearly functional separation through its modular design, is relativelyunproblematic in regards to adding additional manufacturing tolerancesof its individual members, since the closing elements each open in theirrespective seat cleaning positions non-critical in the arranged valvehousing members and therefore danger of collision in the process of thepartially open positions T1, T2 do not exist. For this reason theproposed device needs no adjustable stops for limiting the respectivepartial stroke movements of the closing elements in the process of theirseat cleaning, rather there are conceivable simple end-of-travel limitstops. In this regard a proposal is envisaged that the end-of-travellimit stops of the second actuating piston for the first partially openposition T1 and that of the third actuating piston for the secondpartially open position T2 are done by a stop-ring or housing ringarranged permanently between the actuating piston and axially movable onboth sides.

It is further proposed that the fourth pressurizing medium chamber isconnected according to the stream with a first pressurizing mediumconnection, which is equipped on a control device arranged in theconnection to the main adjustment device. Since according to anadvantageous embodiment this connection is done within the mainadjustment and the individual adjustment devices, in this way the firstpressurizing medium chamber of the main adjustment device can also besupplied with pressurizing medium, so that external pressurizing mediumconnections for controlling the full opening stroke H are not necessaryeither on the main adjustment device nor on the housing of theindividual adjustment device.

Nevertheless a further embodiment is allowed for, alternative to thepreceding proposed solution, to provide the fourth pressurizing mediumchamber with a fourth pressurizing medium connection, which is designedto be on the housing of the individual adjustment devices. Throughretention of the internal connection lines between the first and thefourth pressurizing medium chamber there exists an additionalpossibility for control with this solution, to activate the full openingstroke of the double seat valve over this external fourth pressurizingmedium connection, whereby the first pressurizing medium connection onthe control device is then omitted or can be blinded.

Along with the axial decoupling of the first valve stem or the secondactuating piston from the first actuator stem in the main adjustmentdevice there is a further advantageous embodiment allowed for, toadditionally put into effect a rotating decoupling between theaforementioned members at this decoupling location. As is generallyknown in the axial deformation of a helical spring, as is provided asthe main spring in the main adjustment device, considerable torsionalmoments are transferred from the spring onto its abutment, in this caseon the first actuating piston loaded from this and therefore on thefirst actuator stem. These torsional moments can cause loosening of theactuator stems and adjustment rods which are bolted together. Throughthe proposed rotating decoupling between the main and the individualadjustment devices the aforementioned rotation on the first actuatorstem remains limited; a transfer of a torque on other members in thearea of the individual adjustment devices and the double seat valve isimpossible.

The rotating decoupling proves to be especially advantageous if,according to a further proposal, the frontal end of the first actuatorstem has a header, which engages into a cutout within one of theheadpieces that is formed onto the second actuator stem and that has alarger diameter compared to it. The sliding conditions are therebyimproved in that a plain bearing bush is placed between the header andthe cutout.

In order to be able to realize the axial position of the independentlyactuated first closing element even after the axial decoupling of thefirst actuator stem in the control device, according to a furtherproposal a position indicator rod is provided, which each timeconcentrically penetrates the first actuator stem completely and thesecond actuator stem to the first control rod, which on the one sideends in a control device and on the other side is screwed with itsfrontal end in the second actuator stem and thereby counter secures thescrew connection between the adjustment rod and the actuator stem on afirst end surface of the first control rod with its arranged second endsurface. The proposed jam nut makes difficult or prevents loosening ofthe screw connection between the first control rod and the secondactuator stem in the area of the second individual adjustment device.

The ring channel, which is designed between the position indicator rodon the interior and the first actuator stem, the header, the headpieceand the second actuator stem each on the exterior, is advantageouslyused as a route of transport for the pressurizing medium to the firstpressurizing medium chamber, as well as to the fourth pressurizingmedium chamber, whereby the distribution of the pressurizing medium inthese spaces is done with the appropriate cross holes.

Through the preceding described batch function of the first individualadjustment device working together with the main adjustment devicedesignated for the generation of the full opening stroke H, a reductionof the diameter size of the main adjustment device is possible, so thatthe housing of the main adjustment device and that of the individualadjustment devices can be implicitly designed with the same diameter,whereby according to the requirements the latter must bring a loweractuating force than the main adjustment device. Thereby it is againpossible, as a further proposal shows, to make the housing members ofthe main adjustment device and those of the individual adjustmentdevices from housing rough parts of the same shape, whereby a furthercost reduction results.

The manufacturing costs can be further reduced in that the housingmembers of the main adjustment device and those of the individualadjustment device are each integrally joined together, preferablythrough welding. It is understood that the housing members coming intoquestion can also be connected with each other in a detachable manner.

Overall it has been shown that the proposed device for actuating doubleseat valves, is realized first of all with a so-called modular actuatingconcept and secondly, further cost reducing actions were proposedcompared to the known so-called integrated actuating leading to asignificant reduction of the manufacturing costs which amounts to halfof the previous costs.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the proposed device for actuating double seatvalves according to the invention are represented in the drawing and aredescribed following according to design and function, wherein:

FIG. 1 shows a middle cross-section through a first embodiment of adevice for actuating double seat valves of the generic type according tothe invention, whereby the referenced double seat valve in the closedposition in this reference is arranged below the proposed device and acontrol device (in broken-out section) is arranged above it.

FIG. 2 shows a middle cross-section through the device according to FIG.1, whereby the illustrated device represents the position of themovement dependent members so that these correspond to the closedposition of the two closing elements which are represented in the lowerarea of the illustration in sections.

FIG. 3 also shows a device in middle cross-section and both arrangedclosing elements according to FIG. 2, whereby the members of the devicecoming into question henceforth are found in one of the correspondinglocations of the full open positions of the two closing elements;

FIG. 4 also shows the device in middle cross-section and both arrangedclosing elements according to FIG. 2, whereby the members of the devicecoming into question henceforth are found in one of the correspondinglocation of the seat cleaning positions of the first closing elementdesigned as a sliding piston and

FIG. 5 also shows in middle cross-section the device and both arrangedclosing elements according to FIG. 2, whereby the parts of the devicecoming into question henceforth are found in one of the correspondinglocations of the seat cleaning positions of the second closing elementdesigned as a seat disc;

FIG. 6 a middle cross-section through a second embodiment of theindividual adjustment devices according to the invention, whereby thethird actuating piston is connected with an additional piston and thusthe arranged second individual adjustment device supports a so-called“batch function” and

FIG. 6 a a section from the individual adjustment devices according toFIG. 6 in the area of the screw connection between the third actuatingpiston and the additional piston.

DETAILED DESCRIPTION

The proposed device 100, 200 (FIG. 1) is used for actuating a doubleseat valve, that is essentially made up of a valve housing 1 with afirst and a second valve housing member 1 a or 1 b, two closing elements2 and 4 which move independently to each other using the arrangedadjustment rods 3 a or 4 a in each case, a seat ring 2 which makes aconnection between the valve housing members 1 a, 1 b using its innerconnection orifice 2 c, a lantern housing 6 connecting the second valvehousing member 1 b with the device 100, 200, as well as a control device7, whereby the latter is arranged on the side of the device 100, 200opposite to the double seat valve.

The independently actuated, first closing element 3 designed as asliding piston is equipped on the circumference with a first seat seal 8working exclusively in the radial direction, which is attached to afirst seat surface 2 a (FIG. 2), which is formed from the cylindricalsurface in the seat ring 2 which borders the connection orifice 2 c. Thedependently actuated second closing element 4 designed as a seat dischas in its seat area a second seat seal 9 which works in both the radialand axial direction, and which works together on the second seat surface2 b also designed on seat ring 2. Between the two closing elements 3, 4a leakage chamber 5 is formed which in the fully open position H of thedouble seat valve (FIG. 3) is sealed against its environment by means ofa seal 10 working exclusively in the axial direction, which is arrangedon the end surface of the second closing element 4 facing the leakagechamber 5.

The leakage chamber 5, as well as the adjacent parts impinged by theflow, can be cleaned in the closed as well as in the open position ofthe double seat valve (see also FIGS. 2, 3 along with FIG. 1) by meansof a cleaning solution R which is introduced through a cleaning solutionconnection 11 which is arranged in the area of the lantern housing 6 onthe second control rod 41, preferably a non-specified ring channel,between the first and the second control rods 3 a, 4 a. The removal ofthis type of “externally” introduced cleaning solution R from theleakage chamber 5 is done here by a non-specified connection line whichis arranged in a tubular extension leading through the first valvehousing part 1 a and out of it on the first closing element 3.

The removal of an “internally” introduced cleaning solution by aparticular seat cleaning stream R1, R2 from the internal chamber 5,which is introduced from the valve housing part 1 a or 1 b assigned atany one time during the seat cleaning of the first or the second closingelement 3, 4 (also see for this FIGS. 4 and 5), is done in the samemanner as with the external cleaning introduction R. In the seatcleaning of the first closing element 3, which is designed as a slidingpiston, this is pushed so far in the direction of the first valvehousing member 1 a (FIG. 4), that a first partially open position T1consequently occurs, in which the first seat seal 8 has left theassigned first seat surface 2 a and the first seat cleaning stream R1from the first valve housing member 1 a is generated over the exposedfirst seat surface 2 a in the leakage chamber 5.

For seat cleaning of the second closing element 4, which is designed asa seat disc, this is pushed so far in the direction of the second valvehousing member 1 b (FIG. 5), that in a thus partially open position T2taken from the second closing element 4, the second seat seal 9 left theassigned second seat surface 2 b and the second seat cleaning stream R2from the second valve housing member 1 b arrives into the leakagechamber 5 on the way over the exposed seat surface 2 b.

To limit the amount of cleaning solution in each of the seat cleaningstreams R1, R2 during the seat cleaning, if necessary known cylindricalprojections are provided on the closing elements 3, 4, oriented towardthe leakage chamber 5, which during gapwise removal of the closingelements 3, 4 from their assigned seat surfaces 2 a, 2 b still reachessufficiently far with radial clearance into the connection orifice 2 cwith the respective cylindrical projection and there in each caseforming a so-called choking annular gap. Alternatively the limit of theseat cleaning streams R1, R2 are thus also reached in that theparticular partial stroke is not stationary generated, but ratheroscillating.

To put into effect the preceding briefly illustrated switch movement ofthe closing elements 3, 4 (full opening stroke H, partially openpositions T1 and T2) hence-forth the double seat valve is equipped withthe device 100, 200 according to the invention, which has the mainadjustment device 100 for the opening and closing of the double seatvalve within the scope of the full opening stroke H (FIG. 1) and theindividual adjustment devices 200 for the generation of the partiallyopen positions T1, T2. The main adjustment device 100 corresponds in itsdesign to a so-called standard actuator, with which a double seat valveof the type in question can be opened and closed on its own; Specialfunctions, such as seat cleaning, cannot be done with this standardactuator. The main adjustment device 100 is designed in a manner inregards to its peripheral housing connections and other necessaryconnections, so that when eliminating the individual adjustment devices200 it can be directly connected with a lantern housing 6, which is infact adjusted in length but is otherwise not changed. The end (malethreads) of the first control rod 3 a is in this regard designed in sucha way, that it is complementary to an end section (female threads) of asecond actuator stem 203 of the individual adjustment device 200, aswell as is complementary to an end section of a first actuator stem 103of the main adjustment device 100, with which it is screwed in eachcase, if necessary. The second control rod 4 a continues on above thecleaning solution connection 11 in a third actuator stem 204 designed asa hollow rod and ends in the individual adjustment devices 200.

Since the main adjustment device 100 and the individual adjustmentdevices 200 are axially decoupled from each other in a special operatingcondition of the double seat valve, especially the location of the firstclosing element 3 must be recorded if needed at every point in time, aposition indicator rod 7 a is provided, which each time concentricallypenetrates the first actuator stem 103 completely and the secondactuator stem 203 up to the first control rod 3 a, which ends in thecontrol device on one end and with its frontal end is screwed into thesecond actuator stem 203 which is tightly screwed with the first controlrod 3 a.

For the control of the main adjustment device 100 a first pressurizingmedium connection 7 b is provided on the control device 7 through whicha first pressurizing medium flow D1 is charged or discharged.Alternatively to this the main adjustment device 100 can be chargedusing a fourth pressurizing medium connection 210 arranged on theindividual adjustment devices 200 with an alternate first pressurizingmedium flow D1*. To generate the partially open positions T1, T2 theindividual adjustment devices 200 have a second and a third pressurizingmedium connection 208, 209 available for a second and third pressurizingmedium flow D2, D3.

The housing of the main adjustment device 100 (FIG. 2; the multiplicityof seals of the device are here and in further figures not specifiedindividually) consists of a first and a second housing member 101, 102,which are essentially made from housing rough parts of the same shape. Afirst actuating piston 104 with piston seal is arranged on the firstactuator stem 103 and fixed there with a non-specified nut. Apretensioned main spring 105 finds its abutment on the one end on thefirst actuating piston 104 and on the other end on the first housingmember 101. After the installation of the first actuating piston 104,the first actuator stem 103 and the main spring 105 in both housingmembers 101, 102 the latter are preferably integrally joined together,especially by welding. The seals and guide bushings in housing 101/102of the main adjustment device 100 are also exchangeable after theirfinal assembly. The hollow first actuator stem 103 penetrated by theposition indicator rod 7 a, and the ring channel 106 formed betweenthese two rods 7 a, 103 serve for the transport of the firstpressurizing medium flow D1 or of the first alternate pressurizingmedium flow D1*. In each case both reach through the first cross holes106 a as the first pressurizing medium flow D1.1 (s. FIG. 3) in a firstpressurizing medium chamber 100 a formed between the first actuatorpiston 104 and the second housing member 102, from where they also flowout in the opposite direction.

Below the main adjustment device 100 the individual adjustment devices200 are additively inserted. The latter, seen from top to bottom, aremade up of a first individual adjustment device 200.1 for generation ofthe first partially open position T1 of the first closing element 3 andby a second individual adjustment device 200.2 for generation of thesecond partially open position T2 of the second closing element 4. Thehousings of the individual adjustment devices 200 are formed from athird and a fourth housing member 201, 202, which are made essentiallyfrom housing rough parts of the same shape, and after the assembly ofthe mounting parts are preferably integrally joined together, especiallyby welding.

In the first individual adjustment device 200.1 a second actuatingpiston 205 provided on the circumference with a piston seal is arrangedby which a headpiece 203 a, which is molded on the second actuator stem203 and enlarged in diameter compared to it, engages interlocking andsealing in such a way so that the second actuator stem 203 and thesecond actuating piston 205 can be seen as connected permanentlytogether. A circlip 214 is used for fixing the headpiece 203 a in thesecond actuating piston 205. Between the second actuating piston 205 andthe third housing member 201 a second pressurizing medium chamber 200 ais formed, which is connected with the second pressurizing mediumconnection 208.

Below the second actuating piston 205 a third working piston 206 isarranged with a provided piston seal on the circumference in the fourthhousing member 202, which is positioned moveable in the axial directionin the interior on the third actuator stem 204 which is designed as ahollow rod and is able to be brought with this in the direction of thesecond partially open position T2 on a shaped recess 204 a on the end ofthe actuator stem 204 in a clamped connection. A third pressurizingmedium chamber 200 b is formed between the third actuating piston 206and the fourth housing member 202, which is connected with the thirdpressurizing medium connection 209. A fourth pressurizing medium chamber200 c is circumferentially encompassed by the housing of the individualadjustment device 201/202, on one face side by the second working piston205 and on the other face side by the third working piston 206. Thefourth pressurizing medium chamber 200 c is fed if necessary eitherusing the ring channel 106 and from this by a second pressurizing mediumpartial flow D1.2 (see FIG. 3) below the second cross hole 203 cbranching off from the headpiece 203 a or using the fourth pressurizingmedium connection 210 of the alternate first pressurizing medium flowD1*. In the illustrated exemplary embodiment the fourth pressurizingmedium connection 210 is actually blinded by a sealing plug 211.

Between the headpiece 203 a and the third actuator stem 204 a secondspring 207 is arranged in the area of the second individual adjustmentdevice 200.2 within an expansion of the third actuator stem 204 having ahollow rod shaped design, whose pretensioning is measured so that thesecond closing member 4, designed as a seat disc, is pressed in itsclosing position with sufficient force on the assigned second seatsurface 2 b. In the open position of the double seat valve (FIG. 3) thesomewhat reduced pretensioning is still sufficient, because of aninsignificant elongation of the second spring 207, to press the closingelements 3, 4 together with sufficient force so that the leakage chamber5 is securely sealed from the environment by the seal 10.

The end-of-travel limit of the second actuating piston 205 for the firstpartially open position T1 (FIG. 4) and that of the third actuatingpiston 206 for the second partially open position T2 (FIG. 5) is done bya stop ring 213 axially movable on both sides, which is permanentlyarranged on housings 201/202 between the actuating pistons 205, 206. Thefirst partially open position T1 results unavoidably by the axialdistance between the stop ring 213 and the second actuating piston 205(first partial piston travel a; T1=a), if the possible displacementbetween the headpiece 203 a and the end of the third actuator stem 204(second partial piston travel b) is measured so that a≦b is given (FIG.2). Conformance to the condition a≧b guarantees on the other hand, thatthe closing element 4 is pressed by the headpiece 203 a in the partiallyopen position T1 statically determined by its assigned second seatsurface 2 b, which then supports the headpiece 203 a on recess 204 a andnot directly over the second actuating piston 205 on the stop ring 213.

The possible travel distance of the third actuating piston 206 to itsstop on the stop ring 213 is determined on the exterior by the thirdpartial piston travel c, whereas the third actuating piston 206 cantravel in the interior by a fourth partial piston travel d, which isdesigned inevitably smaller than the third partial piston travel c untilit ends in the clamping connection with the recess 204 a. As a resultthrough the actuation of the third actuating piston 206 results in thesecond partially open position T2, which is determined (T2=c−d) by thedifference [c−d] (FIG. 2).

The first control rod 3 a is screwed with the second actuator stem 203in the area of the second individual adjustment device 200.2 (FIG. 2).In order to prevent or at least to complicate a loosening of this screwconnection, it is counter secured by the position indicator rod 7 a. Forthis presses the latter, which for its part is coaxially screwed in thesecond actuator stem 203, with a second end surface 7 c on a first endsurface 3 b of the first control rod 3 a. Through this the positionindicator rod 7 a forms the immediate continuation of the first controlrod 3 a, so that by this arrangement the respective position of thefirst closing element 3 is securely acquired.

In the frontal end of the first actuator stem 103 reaching into theindividual adjustment devices 200 a header 103 a is screwed in, whichengages into a cutout 203 b within the headpiece 203 a, whose diameteris enlarged compared to it and which is formed onto the second actuatorstem 203. The header 103 a is arranged in the cutout 203 b movable bothin the axial as well as the rotational direction, whereby the axialmovement is limited by a stop face 203 d, which forms the frontal endcircumferential border of the recess 203 b. To reduce the friction aplain bearing bush 212 is provided between the header 103 a and therecess 203 b. Through the pertinent embodiment in the area of the header103 a, the main adjustment device 100 and the individual adjustmentdevices 200 are axially and in the general direction of rotationdecoupled from each other in the direction of the first partially openposition T1.

The double seat valve is transported into its full open position H (FIG.3) if the first pressurizing medium flow D1 of the proposed device isfed through the ring channel 106. The first pressurizing medium flow D1branches out at the first cross hole 106 a into the first pressurizingmedium partial flow D1.1, which arrives in the first pressurizing mediumchamber 100 a of the main adjustment device 100, and into the secondpressurizing medium partial flow D1.2, which almost at the same timeloads the fourth pressurizing medium chamber 200 c of the firstindividual adjustment device 200.1 through the second cross hole 203 c.Alternatively to the preceding described loading of the pressurizingmedium chambers 100 a and 200 c with pressurizing medium, their loadingcan also be done through the fourth pressurizing medium connection 210.In this case the alternate first pressurizing medium flow D1* firstenters into the fourth pressurizing medium chamber 200 c completely, inorder to then divert the first pressurizing medium partial flow D1.1from this through the second cross hole 203 c, the ring channel 106 andthe first cross holes 106 a into the first pressurizing medium chamber100 a.

The two actuating pistons 104 and 205 loaded with pressurizing medium inthis manner take hold directly or indirectly (through header 103 a) withtheir respective opening force, which results from the respectivepressure in the assigned pressurizing medium chamber 100 a, 200 c andeach provided effective piston surface, on the first actuator stem 103and therefore together override the pretensioned force of the mainspring 105. Through the axial decoupling of the arrangement in the areaof the header 103 a/headpiece 203 a combination the grabbing pressureand/or friction forces against the opening movement on the two closingelements 3, 4 can be overridden if necessary by only two secondactuating pistons 205. Seen as a whole both actuating pistons 104, 205in the process of the opening movement override the total resistingforce which results from the pretensioning force of the main spring 105and from the total pressure and/or friction forces, so that the firstindividual adjustment device 200.1 in this movement phase receives thetask of a so-called batch actuator, whereby the preceding describeddiameter reduction of the main adjustment device 100 is justified andachievable.

The seat cleaning of the first closing element 3 (FIG. 4) is done by theintroduction of the second pressurizing medium flow D2 in the secondpressurizing medium chamber 200 a of the first individual adjustmentdevice 200.1 on the route over the second pressurizing medium connection208. Thus the second actuating piston 205 which is loaded withpressurizing medium is pushed down in the partially open position T1=a(cf. also FIG. 2), whereby the assigned first seat surface 2 a isexposed and the first seat cleaning stream R1 from the first valvehousing member 1 a reaches on the way over the gapwise opened seat 2 a/8into the leakage chamber 5. Since the first actuator stem 103 isend-of-travel limited in the direction of the individual adjustmentdevices 200, the header 103 a also remains in its appropriate endposition. Through the axial decoupling between the header 103 a andheadpiece 203 a the second actuating piston 205 can axially slide itselfonto the header 103 a, so that the stop face 203 d loosens itself fromthe later and distances so far until the actuating piston 205 takes itsbearing on the exterior of the stop ring 213. In order to ensure a stopof the actuating piston 205 on the stop ring 213 and not over theheadpiece 203 a on frontal end of the third actuator stem 204, to therecess 204 a, the condition a≦b must be met.

The seat cleaning of the second closing element 4 (FIG. 5) is achievedin that the third pressurizing medium flow D3 is introduced by the thirdpressurizing medium connection 209 into the third pressurizing mediumchamber 200 b of the second individual adjustment device 200.2. Thus thethird actuating piston 206 which is loaded by pressurizing medium movesin the direction toward the stop ring 213. On its travel distance up toresting on this it must overcome the third partial piston travel c (cf.FIG. 2). Beforehand it gets in a clamping connection after the fourthpartial piston travel d with its clamping flat 206 a on recess 204 a, sothat after a stop on the stop ring 213 from the third actuator stem 204and thus the required partially open position T2=c−d is completed fromthe second closing element 4 against the pretension force of the secondspring 207. The latter finds an abutment on the headpiece 203 a, whichsupports itself unmoveablely with its stop face 203 d on the header 103a, since the latter is securely fastened by the first actuator stem 103in connection with the first actuating piston 104 from the pretensioningforce of the main spring 105 in this end position. Through the secondpartially open position T2 the second closing element 4 is removedgapwise from its assigned second seat surface 2 b, so that the secondseat cleaning stream R2 from the second valve housing member 1 b reachesover the gap between the exposed second seat surface 2 b and the secondseat seal 9 into the leakage chamber 5.

In the second individual adjustment device 200.2 inside the individualadjustment devices 200 (FIG. 6), in which the third actuating piston 206with a so-called “batch function” is provided, the latter is connectedtightly, however able to be loosened, on its side facing the secondactuating piston 205 with a smaller diameter additional piston 206.1.The additional piston 206.1 working together with a housing ring 213.1fixed on the housing 201/202 of the individual adjustment device 200forms a fifth pressurizing medium chamber 200 d, which is connected witha third pressurizing medium chamber 200 b formed between the thirdactuating piston 206 and a non-specified bottom member of the fourthhousing member 202. At the same time the additional piston 206.1 has alarger diameter exterior piston section 206.1 a and a smaller diameterinterior piston section 206.1 b, whereby the exterior piston section206.1 a features an external diameter D_(a) and the interior pistonsection 206.1 b an internal diameter D_(i) (FIG. 6 a). The interiorpiston section 206.1 b is sealed on its frontal end by means of seals217 which are coaxially arranged with each other against the thirdactuating piston 206 and screwed with this using a number of boltedconnections 206.2 arranged distributed over its circumference. Theexterior piston section 206.1 a is circumferentially sealed against theshell of a cylindrical recess 213.1 a in the housing ring 213.1 by meansof a first piston seal 215. In the same manner the interior pistonsection 206.1 b is sealed circumferentially in a coaxial through bore213.1 b in the housing ring 213.1 by means of a second piston seal 216.The third pressurizing medium flow D3 is introduced over the thirdpressurizing medium connection 209 first to the third pressurizingmedium chamber 200 b. From there the pressurizing medium reaches over afirst pressurizing medium channel 206 b running between the two seals217 in an axial direction through the third actuating piston 206, inorder to finally reach into a second pressurizing medium channel 206.1 dwhich is running corresponding with these in the additional piston 206.1up to the fifth pressurizing medium chamber 200 d.

The housing ring 213.1 has a circumferential radial projection 213.1 c,with which it is positively fastened in the connection area between thethird and the fourth housing member 201, 202. Between the housing ring213.1 and the third actuating piston 206 a preceding fourth pressurizingmedium chamber 200 c* is designed, in which the fourth pressurizingmedium connection 210 discharges. Through the latter the alternate firstpressurizing medium flow D1* is charged or discharged for implementationof the full opening stroke H for the independently actuated closingelement 3. The preceding fourth pressurizing medium chamber 200 c* isconnected through at least one connection channel 213.1 d with thedesigned fourth pressurizing medium chamber 200 c which is between thesecond actuating piston 205 on one side and the housing ring 213.1 inconnection with the additional piston 206.1 on the other side, which islocated in a part of the housing ring 213.1 containing the cylindricalrecess 213.1 a on the exterior.

The radial projection 213.1 c is designed on its side facing the thirdactuating piston 206 in a manner so that the latter, afterimplementation of the second partial piston travel c (FIG. 6 a), theremeets an end-of-travel limit and thus the corresponding limit of thesecond partially open position T2 within the second individualadjustment device 200.2 is guaranteed.

A corresponding limit of the first partial piston travel a under thecondition a≦b (cf. also FIG. 2) is done by the first individualadjustment device 200.1, which is put into effect by the first partiallyopen position T1 in that the second actuating piston 205 comes to reston the housing ring 213.1 which is permanently located on the housing201/202. Under the condition a≧b after implementation of the firstpartially open position T1 a modified headpiece 203 a* of the secondactuator stem 203 (not specified) activated by the first closing element3 comes to rest on recess 204 a (also not specified), as was alreadydescribed in connection with the first embodiment of the individualadjustment devices 200 according to the FIGS. 1 to 5, especiallyaccording to FIG. 4.

The third actuating piston 206 strikes over the clamping flat 206 a onthe recess 204 a (cf. also FIG. 5), to produce the completion of thesecond partially open position T2 of the second closing element 4 in oneor the other directions. The axial extension of the end of the modifiedheadpiece 203 a* facing the third actuating piston 206 makes itnecessary to provide the additional piston 206.1 with a coaxial pistonbore 206.1 c, which surrounds the modified headpiece 203 a* withclearance outside.

REFERENCE NUMBERS OF THE ABBREVIATIONS USED

-   1 valve housing-   1 a first valve housing member-   1 b second valve housing member-   2 seat ring-   2 a first seat surface-   2 b second seat surface-   2 c connection orifice-   3 first closing element-   3 a first control rod-   3 b first end surface-   4 second closing element-   4 a second control rod-   5 leakage chamber-   6 lantern housing-   7 control device-   7 a position indicator rod-   7 b first pressurizing medium connection-   7 c second end surface-   8 first seat seal (radial)-   9 second seat seal (radial, axial)-   10 seal (axial)-   11 cleaning solution connection-   100 main adjustment device-   100 a first pressurizing medium chamber-   101/102 main adjustment device housing-   101 first housing member-   102 second housing member-   103 first actuator stem-   103 a header-   104 first actuating piston-   105 main spring-   106 ring channel-   106 a first cross hole-   200 individual adjustment device-   200.1 first individual adjustment device-   200.2 second individual adjustment device-   200 a second pressurizing medium chamber-   200 b third pressurizing medium chamber-   200 c fourth pressurizing medium chamber-   200 c* preceding fourth pressurizing medium chamber-   200 d fifth pressurizing medium chamber-   201/202 individual adjustment device housing-   201 third housing member-   202 fourth housing member-   203 second actuator stem-   203 a headpiece-   203 a* modified headpiece-   203 b cutout-   203 c second cross hole-   203 d stop face-   204 third actuator stem-   204 a recess-   205 second actuating piston-   206 third actuating piston-   206 a clamping flat-   206 b first pressurizing medium channel-   206.1 additional piston-   206.1 a exterior piston section-   206.1 b interior piston section-   206.1 c coaxial piston bore-   206.1 d second pressurizing medium channel-   206.2 bolted connection-   207 second spring-   208 second pressurizing medium connection-   209 third pressurizing medium connection-   210 fourth pressurizing medium connection-   211 sealing plug-   212 plain bearing bush-   213 stop ring-   213.1 housing ring-   213.1 a cylindrical cutout-   213.1 b coaxial through-bore-   213.1 c radial projection-   213.1 d connection channel-   214 circlip-   215 first piston seal-   216 second piston seal-   217 seal-   a first partial piston travel-   b second partial piston travel-   c third partial piston travel-   d fourth partial piston travel-   D1 first pressurizing medium flow-   D1.1 first pressurizing medium partial flow-   D1.2 second pressurizing medium partial flow-   D1* alternate first pressurizing medium flow-   D2 second pressurizing medium flow-   D3 third pressurizing medium flow-   D_(a) outer diameter-   D_(i) inner diameter-   H full opening stroke (fully open position)-   R cleaning solution-   R1 first seat cleaning stream-   R2 second seat cleaning stream-   T1 first partially open position (T1=a)-   T2 second partially open position (T2=c−d)

The above disclosure is intended to be illustrative and not exhaustive.This description will suggest many variations and alternatives to one ofordinary skill in this art. All these alternatives and variations areintended to be included within the scope of the claims where the term“comprising” means “including, but not limited to”. Those familiar withthe art may recognize other equivalents to the specific embodimentsdescribed herein which equivalents are also intended to be encompassedby the claims.

Further, the particular features presented in the dependent claims canbe combined with each other in other manners within the scope of theinvention such that the invention should be recognized as alsospecifically directed to other embodiments having any other possiblecombination of the features of the dependent claims. For instance, forpurposes of claim publication, any dependent claim which follows shouldbe taken as alternatively written in a multiple dependent form from allprior claims which possess all antecedents referenced in such dependentclaim if such multiple dependent format is an accepted format within thejurisdiction (e.g. each claim depending directly from claim 1 should bealternatively taken as depending from all previous claims). Injurisdictions where multiple dependent claim formats are restricted, thefollowing dependent claims should each be also taken as alternativelywritten in each singly dependent claim format which creates a dependencyfrom a prior antecedent-possessing claim other than the specific claimlisted in such dependent claim below.

This completes the description of the preferred and alternateembodiments of the invention. Those skilled in the art may recognizeother equivalents to the specific embodiment described herein whichequivalents are intended to be encompassed by the claims attachedhereto.

1. Device for actuating double seat valves, especially for the food andbeverage industry, comprising a first closing element (3) and a secondclosing element (4), the first and second closing elements (3,4) movableindependently of one another; a leakage chamber (5), the leakage chamber(5) being enclosed by the first and second closing elements (3,4), theleakage chamber (5) being connected over at least one path of travelwith the environment of a double seat valve, the first closing element(3) being designed as a sliding piston, after a partial stroke the firstclosing element (3) coming to rest on the second closing element (4),the second closing element designed as a seat disc, the second closingelement (4) having a further opening movement, the partial stroke andthe further opening movement causing a full open position (H); a firstcontrol rod (3 a, 203) and a second control rod (4 a, 204), the firstand second control rods (3 a, 203, 4 a, 204) fitting into one another ina telescoping manner and extending outward on the side of the secondclosing element (4) from a valve housing (1), the first closing element(3) having a first partially open position (T1) and the second closingelement (4) having a second partially open position (T2), the full openposition (H) being generated through a main adjustment device (100) anindividual adjustment device (200) comprising a first individualadjustment device (200.1) and a second individual adjustment device(200.2), the first individual adjustment device (200.1) generating thefirst partially open position (T1) of the first closing elements (3) andthe second individual adjustment device (200.2) generating the secondpartially open position (T2) of the second closing element (4); and anadjustment of the first and second closing elements (3,4) being done bya first actuating piston (104), a second actuating piston (205) and athird actuating piston (206 or 206/206.1) loaded by a pressurizingmedium acting on the first and second control rods (3 a, 203; 4 a, 204),characterized in that the first and second individual adjustment devices(200; 200.1, 200.2) are designed independently and are additivelyinserted between the main adjustment device (100) and the valve housing(1), the third actuating piston (206; 206/206.1) being positionedaxially moveable on the second control rod (4 a, 204), the secondcontrol rod (4 a, 204) being hollow, the second control rod (4 a, 204)surrounding the first control rod (3 a, 203) and able to be brought withthe first control rod (3 a, 203) in the direction of the secondpartially open position (T2) in a clamping connection, the secondactuating piston (205) being permanently connected on one side with thefirst control rod (3 a, 203) which adjusts the first closing element(3), the first control rod (3 a, 203) being alternatively directly orindirectly axially movable positioned on a first actuator stem (103) ofthe main adjustment device (100) and able to be brought with the firstactuator stem (103) in the direction of the full open position (H) in aclamping connection, and the second actuating piston (205) being able tobe loaded with pressurizing medium on each of its two piston surfaces.2. Device according to claim 1, characterized, in that the first andsecond individual adjustment devices (200.1, 200.2) are arranged in asingle housing comprising a third housing member (201) and a fourthhousing member (202), a second actuating piston (205), a third actuatingpiston (206 or 206/206.1), the third and fourth housing members (201,202) and the second and third actuating pistons (205, 206 or 206/206.1)forming a second pressurizing medium chamber (200 a), a thirdpressurizing medium chamber (200 b) and a fourth pressurizing mediumchamber (200 cor 200 c/200 c*). each of the second, third and fourthpressurizing medium chambers (200 a, 200 b, 200 c or 200 c/200 c*) beingable to be controlled independently of each other, the secondpressurizing medium chamber (200 a) being between the second actuatingpiston (205) and the third housing member (201), the third pressurizingmedium chamber (200 b) being between the third actuating piston (206)and the fourth housing member (202) and the fourth pressurizing mediumchamber (200 c or 200 c/200 c*) being between the second and thirdactuating pistons (205, 206).
 3. Device according to claim 1,characterized in that the first actuator stem (103, 103 a) of the mainadjustment device (100) extends out from the main adjustment device(100) in the direction of the first and second individual adjustmentdevice (200; 200.1, 200.2) and there is guided moveable axially into thefront end of a second actuator stem (203, 203 a or 203 a*), the secondactuator stem being permanently connected with the first control rod (3a), up to a stop face (203 d).
 4. Device according to claim 1,characterized in that the third actuating piston (206) on its sidefacing the second actuating piston (205) is connected tightly with asmaller diameter additional piston (206.1), but the third actuatingpiston (206) is however able to be loosened, the additional piston(206.1) working together with a housing ring (213.1) fixed on third andfourth housing members (201/202) of the individual adjustment device(200) forms a fifth pressurizing medium chamber (200 d), the fifthpressurizing medium chamber (200 d) is connected with a thirdpressurizing medium chamber (200 b), the third pressurizing mediumchamber formed between the third actuating piston (206) and the fourthhousing member (202), and that with the introduction of a thirdpressurizing medium flow (D3) to the third pressurizing medium chamber(200 b) an additional force affecting the additional piston (206.1)results additionally in the fifth pressurizing medium chamber (200 d),which additively superimposes on a force affecting the third actuatingpiston (206).
 5. Device according to claim 4, characterized in that theadditional piston (206.1) has a larger diameter exterior piston section(206.1 a) and a smaller diameter interior piston section (206.1 b), thatthe interior piston section (206.1 b) is sealed on its frontal end fromthe third actuating piston (206) and the interior piston section (206.1b) is screwed with the third actuating piston (206), that the exteriorpiston section (206.1 a) is sealed on its circumference from the shellof a cylindrical cutout (213.1 a) in the housing ring (213.1) theinterior piston section (206.1 b) is sealed on its circumference in acoaxial through bore (213.1 b) in the housing ring (213.1), and that ina connection area of the third actuating piston (206) with theadditional piston (206.1) are arranged in the third actuating piston(206) a first pressurizing medium channel (206 b) and in the additionalpiston (206.1) a second pressurizing medium channel (206.1 d), whichcorrespond with one another and connect the third pressurizing mediumchamber (200 b) and the fifth pressurizing medium chamber (200 d) withone another permeable to the pressurizing medium.
 6. Device according toclaim 4, characterized in that the housing ring (213.1) has a radialprojection (213.1 c) on its circumference, with which the housing ring(213.1) is fixed interlocking in a connection area between the third andfourth housing members (201, 202).
 7. Device according to one of theclaim 4, characterized in that a fourth pressurizing medium connection(210) for an alternate first pressurizing medium flow (D1*) for loadingof the second actuating piston (205) located in the third housing member(201) discharges in a preceding fourth pressurizing medium chamber (200c*) in an area between the third actuating piston (206) and the housingring (213.1), and that the preceding fourth pressurizing medium chamber(200 c*) is connected with the fourth pressurizing medium chamber (200c) formed between the second actuating piston (205) on one side and thehousing ring (213.1) in connection with the additional piston (206.1) onthe other side through at least one connection channel (213.1 d), whichis located in an exterior part of the housing ring (213.1) containing acylindrical cutout (213.1 a).
 8. Device according to claim 1,characterized in that an end-of-travel limit of the second actuatingpiston (205) for the first partially open position (T1) and that of thethird actuating piston (206; 206/206.1) for the second partially openposition (T2) is done by a stop ring (213) or a housing ring (213.1),axially moveable on both sides, and permanently located on third andfourth housing members (201/202) between the second and third actuatingpistons (205, 206).
 9. Device according to claim 2, characterized inthat the fourth pressurizing medium chamber (200 c) is connectedaccording to a stream with a first pressurizing medium connection (7 b),which is provided with a control device (7) located in a connection tothe main adjustment device (100).
 10. Device according to claim 2,characterized in that the fourth pressurizing medium chamber (200 c) isconnected in the direction of a stream to a fourth pressurizing mediumconnection (210), which is proved on the third and fourth housingmembers (201/202) of the individual adjustment device (200).
 11. Deviceaccording to claim 9, characterized in that the first pressurizingmedium connection (7 b) is also additionally connected in the directionof the stream with a first pressurizing medium chamber (100 a) of themain adjustment device (100).
 12. Device according to claim 1,characterized in that the first actuator stem (103) is arranged able torotate against the second actuating piston (205) or with a secondactuator stem (203, 203 a or 203 a*) connected with this.
 13. Deviceaccording to claim 12, characterized in that a frontal end of the firstactuator stem (103) supports a header (103 a), which engages in a cutout(203 b) inside a headpiece (203 a or 203 a*) formed on the secondactuator stern (203), the headpiece (203 a or 203 a*) having a diameterenlarged in comparison to the second actuator stem (203).
 14. Deviceaccording to claim 13, characterized in that a plain bearing bush (212)is located between the header (103 a) and the cutout (203 b).
 15. Deviceaccording to claim 1, characterized in that the first control rod (3 a)is screwed with the second actuator stem (203) in the area of the secondindividual adjustment device (200.2), that a position indicator rod (7a) is provided which each time concentrically penetrates a firstactuator stem (103, 103 a) completely and the second actuator stem (203,203 a or 203 a*) up to the first control rod (3 a), which ends on oneside in a control device (7) and on the other side is screwed into thesecond actuator stem (203) with its frontal end and thereby countersecures the screw connection with its assigned second end surface (7 c)between the control rod and the first control rod (3 a, 203) of a firstend surface (3 b).
 16. Device according to claim 15, characterized inthat the position indicator rod (7 a) forms a continuous ring channel(106) with the first actuator stem (103), a header (103 a), a headpiece(203 a; 203 a*) and the second actuator stem (203), each of which itsurrounds in the named sequence, which branches over a first cross hole(106 a) in a first pressurizing medium chamber (100 a) of the mainadjustment device (100) and over a second cross hole (203 c) in a fourthpressurizing medium chamber (200 c) of the individual adjustment device(200).
 17. Device according to claim 1, characterized in that a housingmember (101, 102) of the main adjustment device (100) and each (201,202) housing of the individual adjustment devices (200) are made fromhousing rough parts of the same shape.
 18. Device according to claim 1,characterized in that a housing member (101, 102) of the main adjustmentdevice (100) and each (201, 202) housing of the individual adjustmentdevices (200) are each integrally joined together.
 19. Device accordingto claim 1, characterized in that the first, second and third actuatingpistons (104, 205, 206, 206/206.1) are made of corrosion resistant lightalloy metal.